This is not a journey through the streets of Lisbon to arrive at a sociological study. It is a journey down channels of memory, a dérive that opens the eye to a psychogeographical encounter, to a serendipitous moment, to the slipping of time and the pursuit of the poetic. There are no people on this dérive, well, no people that are recognisable, that is. They remain a mystery, their identities just out of sight. The opening image sets the tone, starts the journey. I found the old woman descending the stairs into the Metro oddly disturbing; she’s like the small red figure in Nicolas Roeg’s film, Don’t Look Now. The large red M sign to her right takes hold of the imagination. M for madness; M for murder; M for meander. The moment stayed with me as I followed her underground.

Cities are more than a palimpsest of histories; they are Borgesian theatres, where fact and fiction pass through each other.